IL6 and Cognitive impairment: Hennezel et al. (2017) revealed that the levels of Alistipes putredinis and Alistipes finegoldii possess a moderate-to-strong correlation with IL-6, TNF-α and IL-1 production. Another study showed that the Alistipes genus participated in prompting inflammation and tumorigenesis in an IL-6-dependent manner (Moschen et al., 2016). However, there was no significant correlation between Alistipes and IL-1, IL-6 in this study, and a negative correlation between Alistipes and TNF-α. Therefore, Alistipes can aggravate cognitive impairment by other ways than inflammatory response.